On the very same day as Obama’s NAACP address, one of the country’s most distinguished African-American scholars, Professor Henry Lewis Gates of Harvard University in Cambridge, Mass., was arrested for “disorderly conduct” on his front porch, a short walk from campus. It was alleged that Professor Gates had spoken angrily to a white police officer who had suspected Gates of breaking into what the professor told the officer was his own home. (With the help of another man, Gates, returning home from an overseas trip, had forced open the jammed front door to his house, leading a passerby to call the police.) The white officer arrested the black professor, handcuffed him, and took him into custody.

Many people, especially peoples of color, saw the incident as one more example of the indignities blacks continue to endure every day in America. After the historic Obama victory, they felt that perhaps the country, in a self-congratulatory mood, had patted itself on the back too soon. Maybe the long, hard struggle for racial justice was not over.

In reading Patricia Sullivan’s superb new history, Lift Every Voice: The NAACP and the Making of the Civil Rights Movement, one is reminded just how long and hard that struggle has been. While many are aware of the celebrated events of the 1950s and ’60s – the Montgomery bus boycott, the sit-ins, the March on Washington – the 20th-century race reform campaign began long before those iconic episodes.

One of the most striking aspects of Sullivan’s elegantly written book is the extent to which it compels one to realize that the history of the NAACP and the history of 20th-century America are inextricably linked. In exploring this connection, Sullivan, who teaches history at the University of South Carolina, has produced a compelling, exhaustively researched account that sweeps across much of the last century.

Sullivan presents countless tales that reveal the determination African-Americans demonstrated over many decades to effect change in a country that systematically denied them basic rights: 10,000 black citizens marching silently down New York’s Fifth Avenue during World War I to protest a vicious race riot in East St. Louis, Ill.; downtrodden yet optimistic black voters in the north streaming into FDR’s Democratic Party in the 1930s; energized black soldiers fighting oppression at home and abroad during World War II; adroit African-American leaders deploying the democratic rhetoric of the cold war to advance their cause in the 1940s.

As the transformative developments of the 20th century unfolded at home and abroad, Sullivan shows how the NAACP played a key role in the effort to abolish discrimination in voting, education, employment, and housing. The association approached its task in a variety of ways: by working to pass federal legislation; by laboring in the courts – often in hostile Southern courtrooms; and by convincing ordinary African-Americans to work for change in their communities.

In the NAACP’s early years, a key aim was the passage of federal antilynching legislation. NAACP officials hoped a federal law would reduce the number of lynchings, which plagued blacks, especially in the rural South. The barbaric practice had claimed thousands of black lives since the turn of the century – and the murderers almost always escaped punishment.

Sullivan’s harrowing descriptions of these brutal crimes, which local authorities typically ignored or even supported, remind us of the perils black Americans confronted daily throughout much of the 20th century. While federal antilynching legislation never became law – the NAACP could not overcome Southern opposition in Congress – the effort to enact legislation helped to galvanize support for the association.

By the time Sullivan reaches her concluding chapters, which consider the victories of the postwar years – the 1954 verdict in Brown v. Board of Education being the most significant – readers will appreciate how arduous and heroic the struggle for racial justice has been. One will also recognize just how important the NAACP has been in helping America become a more just society, even as one acknowledges – or should – that there is still much work to be done.